在Typescript中只返回一次数组的值列表

const arr = [1, 2, 3, 4, 5];
let isReturned = false;

const result = arr.map((value) => {
  if (!isReturned) {
    isReturned = true;
    return value;
  }
});

console.log(result); // [1]

const arr = [1, 2, 3, 4, 5];
let isReturned = false;

const result = arr.filter((value) => {
  if (!isReturned) {
    isReturned = true;
    return true;
  }
  return false;
});

console.log(result); // [1]

const arr = [1, 2, 3, 4, 5];
let result: number[] = [];

for (const value of arr) {
  result.push(value);
  break;
}

console.log(result); // [1]